Lubricating and sealing fluid



Patented Sept. 8, 1931 UNITED STATES PATENT OFFICE FREDERICK C. NONAMAKER, OF GLOUCESTER CITY, NEW JERSEY, ASSIGNOR TO WELS- IBAOH COMPANY, OF GLOUCESTER CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY LUIBR-ICATING AND SEALING FLUID No Drawing.

. The present invention relates broadly to the art of lubricating and sealing fluids adapted for use in compressors and similar apparatus, and more particularly to a fluid of this character especially adapted for use in refrigeration systems.

In refrigeration systems of the type commonly in use at the present time, there is utilized a mechanical pressure-producing means usually designated as a compressor and effective for producing the desired pressure conditions on the gaseous refrigerant. Considerable difiiculty has heretofore been experienced in the operation of such compressors in preventing either the leakage of the refrigerant under pressure outwardly through the stuffing box'onboxes or the leakage of air inwardly into the system. The first condition is objectionable due to the loss of refrigerant, and the second condition is objectionable not only because it produces a continuously changing condition within the system, but because it increases the moisture present in proportion to the amount of mois- 2 ture in the air drawn in. In an effort to overcome this condition, it has heretofore been proposed to provide a lubricating and sealing fluid effective for maintaining a constant seal on the compressor. While a large number of different liquids and compositions have been proposed for this purpose, it has been found that particularly beneficial results are obtained by a mixture of glycerine and ethyleneglycol. Both of these ingredients are 3 members of the alcohol series, glycerine being a tri-hydric alcohol and glycol a di-hydric alcohol. The combination is of advantage since glycerine alone has high viscosity at low temperatures, thereby requiring a high watt load on the motor which drives the compressor in starting. Glycol alone possesses practically no lubricating properties, and

therefore, could not be used exclusive of some.

lubricant. These ingredients have been combined in the proportion of substantially 79% glycerine to 21% of glycol.

In the use of compressors employing such a lubricating and sealing material, I have observed a deposit in the system, and particularly in the compressor parts, which deposit Application filed March 9, 1927. Serial No. 174,104.

very much resembles a copper deposit. It has heretofore been assumed by those skilled in the art that a chemical reaction takes place in systems of this character by reason of which copper was deposited from the coils onto the various ferrous parts. I have found, however, that this compound is due largely to oxidation of ferrous material in the presence of the water in the system. A glycerine-glycol combination possesses extremely deliquescent properties and rapidly absorbs moisture, this moisture being efi'ective for oxidizing the ferrous materials as set forth.

In some cases, the deposit has become so pronounced as to produce objectionable binding of the compressor parts, seriously interfering with the efficiency of thesystem and resulting in actual deposition on such parts to an extent preventing effective operation.

Of the refrigerants utilized at the present time, sulphur dioxide and ethyl chloride are the most important in apparatus of the expansion type. With either of these refrigerants, or in refrigeration systems generally, it is desirable to prevent the production of an acid condition, as such acid condition reacts destructively on the operating parts, and in many cases is as objectionable as the oxidation, of the character referred to, it-

' self. As the result of a series of experiments,

I have found that while the oxidation may be prevented by the application either of acid compounds or of compounds resulting in the production of an acid condition, such a treatment is objectionable for the reasons referred Uri to. In accordance with the present inven tion, therefore, I propose to utilize in a lubricating compound a reagent preferably of an alkaline nature having either actual reducing properties, where it is to be added to systems which have been inuse for some time, or having properties inhibiting oxidation where intended for use in freshly installed systems.

I have found that reagents effective for this purpose and having alkaline characteristics as referred to may be chosen from a large number, of different groups, including sulphides and sulphites, thlosulphates, comfore, the mixture with a lubricating body ofthe alcohol series, and preferably comprising pounds of the phenol gallol which is a tri-hy pounds oup such 'as' pyro- 'cp enol, andcoma refrigerant, sulphides are objectionable by reason of the odorous compounds which. they produce with the ethyl chloride, .mercaptans (fill: substances similar thereto resulting there- In all cases, it is desirable that the reagent utilized be soluble in the lubricating and sealing fluid, and for this reason, potassium sulphite is much more effective than sodium sulphite, although either may be utilized in,

accordance with the present invention. When the thiosulphates are utilized, I have found that the sodium thiosulphate'is suflieiently soluble to permit its use.'

The present invention contemplates, therea tri-hydric alcohol, such as glycerine, and a di-hydric alcohol, such as glycol, of an ingredient or reagent soluble therein and actmg to prevent oxidation. I am not aware that heretofore in the art, it has been proposed to combine with a lubricating and sealnig fluid an ingredient or reagent efiective for either reducing or inhibiting oxidation. Certain advantages of the present invention, therefore, arise broadly from the addition to a lubricating and sealing fluid, capable of use in refrigerating systems, of an ingre dient or reagent having the characteristics referred to. V

It will be apparent that the amount of the ingredient added in accordance with the present invention may vary in accordance with whether use is made of it in a new structure in which the. h .droxyl is; present. Where ethyl c ride is utilized as.

1,saa,44a-

cating body of the a cohol series liquid at normal temperatures having sodium thio-- sulphate in solution therein efiective for reducing oxidation.

In testimony whereof I have hereunto set my hand. FREDERICK C. NONAMAKER.

in which oxidation has not occurred, or in an old structure in which considerable oxidation has alread manifested itself. In the first instance y sli htly more-thana trace of the oxidation inhi iting ingredient is required, while in the latter case, the percentage may vary from a trace up to a substantial amount. Although acid reagents may be utilized as herein pointed out, the alkaline reagents are preferable under most conditions. One example of a mixture which may be utilized in accordance with the present invention comprises to 80 per cent. of lycerin, 20 to 30 per cent. of lycol and 1 mm a trace to 5 per cent of soil potassium sulphite is utilized, the percentage may be increased". Substantially the same percentages may be utilized'when the inhibiting ingredient comprises either sodium or potassium thiosulphate. 4

Still other advantages of the inyention aiisc from the addition to a lubricating and sealing fluid of an ingredient or reagent of alkaline characteristics and preferably soluble in the lubricating compound being" 1 utilized. I a

um sulphite. If 

